PIX version 6.2 supports NTP, enabling the PIX Firewall to act as an NTP client and synchronize its time to a network time server. This enables the PIX to maintain precise network time for logging and certificate revocation list (CRL) validation. NTP server mode is not supported because the firewall would have to allow incoming requests to open ports, which is a security risk.
PIX version 6.2 supports version 3 of NTP as this is currently the most common version in use and is the highest version supported by Cisco IOS software. The NTP authentication mechanism uses MD5 and is compatible with Cisco IOS software.
Hope it helps.
Steve
